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javaimagejavax.imageio

getSubimage gives me expection null


I'm trying to make chess game with java and I got image from google for pieces. Now I want to cut it to 6*2 images(Black and White ones). But I can't figure out what is wrong with this one.

    public static final String PIECES_IMAGE_PATH = "Images/chess_pieces.png";
    public static final int PIECE_IMAGES_INROW = 6;
    public static final int PIECE_IMAGE_ROWS = 2;

BufferedImage[][] pieceIcons;

    private void setupPieceImages(){
        try {
            BufferedImage image = ImageIO.read(new File(Config.PIECES_IMAGE_PATH));

            int pieceImageWidth = image.getWidth()/Config.PIECE_IMAGES_INROW;
            int pieceImageHeight = image.getHeight()/Config.PIECE_IMAGE_ROWS;
            for(int x = 0; x < pieceImageHeight; x++){
                for(int y = 0; y < pieceImageWidth; y++){
                    try{
                        pieceIcons[x][y] = image.getSubimage(x*pieceImageHeight,y*pieceImageWidth,pieceImageWidth,pieceImageHeight);
                    }catch(Exception e){
                        System.out.println("Error1: "+e.getMessage());
                    }
                }
            }
        }catch(Exception e){
            System.out.println("error2: "+e.getMessage());
        }
    }

Any idea why I keep getting Expection error1: null


Solution

  • I'm not sure why you would iterate over the amount of width/height, but I suppose you want to iterate over 2 rows of 6 columns each (or 6 columns of 2 rows each in this case):

    public static final String PIECES_IMAGE_PATH = "Images/chess_pieces.png";
    public static final int PIECE_IMAGES_INROW = 6;
    public static final int PIECE_IMAGE_ROWS = 2;
    
    
    public static void main(String args[]) {
        BufferedImage[][] pieceIcons = new BufferedImage[PIECE_IMAGES_INROW][PIECE_IMAGE_ROWS];
    
        try {
            BufferedImage image = ImageIO.read(new File(Try.class.getResource(PIECES_IMAGE_PATH).toURI()));
    
            int pieceImageWidth = image.getWidth()/PIECE_IMAGES_INROW;
            int pieceImageHeight = image.getHeight()/PIECE_IMAGE_ROWS;
            for(int x = 0; x < PIECE_IMAGES_INROW; x++){
                for(int y = 0; y < PIECE_IMAGE_ROWS; y++){
                    try{
                        pieceIcons[x][y] = image.getSubimage(x*pieceImageWidth,y*pieceImageHeight,pieceImageWidth,pieceImageHeight);
                    }catch(Exception e){
                        System.out.println("Error1: "+e.getMessage());
                    }
                }
            }
        }catch(Exception e){
            System.out.println("error2: "+e.getMessage());
        }
    }
    

    The error you were getting seems to be related to Error1 and that could be an indexOutOfBoundsException in case you initialized pieceIcons with an unexpected max amount of x/y during runtime.